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2.
Journal of Thermal Analysis and Calorimetry - The present study summarizes a two-dimensional (2D) numerical simulation of a phase change material (PCM) melting/solidification processes in a square...  相似文献   
3.
Olive oil is an important product in the Mediterranean diet, due to its health benefits and sensorial characteristics. Picholine marocaine is the most cultivated variety in Morocco. The present research aims to evaluate the phenolic compounds, vitamin E and fatty acids of commercial Picholine marocaine virgin olive oils (VOOs) from five different North Moroccan provinces (Chefchaouen, Taounate, Errachidia, Beni Mellal and Taza), using HPLC-photodiode array (PDA)/electrospray ionization (ESI)-MS, normal phase (NP)-HPLC/ fluorescence detector (FLD) and GC-flame ionization detector (FID)/MS, respectively. The obtained results showed an average content of 130.0 mg kg−1 of secoiridoids (oleuropein aglycone, 10-hydroxy-oleuropein aglycone and ligstroside aglycone, oleocanthal and oleacein), 108.1 mg kg−1 of phenolic alcohols (tyrosol and hydroxytyrosol), 34.7 mg kg−1 of phenolic acids (caffeic acid, ferulic acid and elenolic acid), and 8.24 mg kg−1 of flavonoids (luteolin, luteolin glucoside, apigenin). With regard to vitamin E, α-tocopherol was the most abundant vitamin E (57.9 mg kg−1), followed by α-tocotrienol (2.5 mg kg−1), γ-tocopherol (4.5 mg kg−1) and β-tocopherol (1.9 mg kg−1), while δ-tocopherol was not detected. Moreover, 14 fatty acids were found and, among them, oleic acid (76.1%), linoleic acid (8.1%) palmitic acid (8.7%) and stearic acid (2.5%) were the major fatty acids detected. Finally, heat map and principal component analysis allowed us to classify the studied provinces in terms of VOO chemical composition: Chefchaouen (tyrosol and hydroxytyrosol), Taounate (oleuropein aglycone), Errachidia (ferulic acid, w-3 and w-6), Beni Mellal (oleocanthal) and Taza (luteolin and oleic acid).  相似文献   
4.
Let be a locally compact group, let be its group algebra, let be its usual measure algebra, let be the second dual of with an Arens product, and let be the conjugate of the space of bounded, left uniformly continuous, complex-valued functions on with an Arens-type product. We find all the finite-dimensional left ideals of these algebras. We deduce that such ideals exist in and if and only if is compact, and in (except those generated by right annihilators of ) and if and only if is amenable.

  相似文献   

5.
M. Filali 《Semigroup Forum》1996,52(1):381-388
Let βS be the Stone-Ĉech compactification of an infinite discrete cancellative semigroupS. The set of points in the growth βS/S at which right cancellation holds in βS is shown to be dense in βS/S. It is then deduced that these type of points also form a dense subset ofUG/G, whenG is a non-compact locally compact abelian group andUG is its uniform compactification.  相似文献   
6.
New homo- and heterometallic, hexa- and pentanuclear complexes of formula {[Cu2(mpba)2(H2O)F][Cu(Me5dien)]4}(PF6)(3).5H2O (1), {[Cu2(Me3mpba)2(H2O)2][Cu(Me5dien)]4}(ClO4)(4).12H2O (2), {[Cu2(ppba)2][Cu(Me5dien)]4}(ClO4)4 (3), and [Ni(cyclam)]{[Cu2(mpba)2][Ni(cyclam)]3}(ClO4)(4).6H2O (4) [mpba=1,3-phenylenebis(oxamate), Me3mpba=2,4,6-trimethyl-1,3-phenylenebis(oxamate), ppba=1,4-phenylenebis(oxamate), Me5dien=N,N,N'N' ',N' '-pentamethyldiethylenetriamine, and cyclam=1,4,8,11-tetraazacyclotetradecane] have been synthesized through the use of the "complex-as-ligand/complex-as-metal" strategy. The structures of 1-3 consist of cationic CuII6 entities with an overall [2x2] ladder-type architecture which is made up of two oxamato-bridged CuII3 linear units connected through two m- or p-phenylenediamidate bridges between the two central copper atoms to give a binuclear metallacyclic core of the cyclophane-type. Complex 4 consists of cationic CuII2NiII3 entities with an incomplete [2x2] ladder-type architecture which is made up of oxamato-bridged CuIINiII and CuIINiII2 linear units connected through two m-phenylenediamidate bridges between the two copper atoms to give a binuclear metallacyclophane core. The magnetic properties of 1-3 and 4 have been interpreted according to their distinct "dimer-of-trimers" and "dimer-plus-trimer" structures, respectively, (H=-J(S1A.S3A+S1A.S4A+S2B.S5B+S2B.S6B)-J'S1A.S2B). Complexes 1-4 exhibit moderate to strong antiferromagnetic coupling through the oxamate bridges (-JCu-Cu=81.3-105.9 cm-1; -JCu-Ni=111.6 cm-1) in the trinuclear and/or binuclear units. Within the binuclear metallacyclophane core, a weak to moderate ferromagnetic coupling (J'Cu-Cu=1.7-9.0 cm-1) operates through the double m-phenylenediamidate bridge, while a strong antiferromagnetic coupling (J'Cu-Cu=-120.6 cm-1) is mediated by the double p-phenylenediamidate bridge.  相似文献   
7.
The title compound, C19H15NO6, contains a planar isoxazole ring. An intramolecular hydrogen bond is formed between the OH group attached to a phenyl ring and a carbonyl O atom.  相似文献   
8.
M. Filali 《Semigroup Forum》1994,48(1):163-168
LetG be a discrete abelian group,Ĝ the character group ofG, andl (G)* the conjugate ofl (G) equipped with an Arens product. In many cases, we can find unitary functionsf such that χf is almost convergent to zero for all χ∈Ĝ. Some of these functions are then used to produce elements μ∈l (G)* such that γμ=0 whenever γ is an annihilator ofC 0(G). Regarded as Borel measures on βG, these elements satisfyxμ=0 for allx∈βG/G. They belong to the radical ofl (G)*, and each of them generates a left ideal ofl (G)* that contains no minimal left ideal.  相似文献   
9.
We construct two d-dimensional independent diffusions Xta=a+∫0tu(Xsa,s)ds+νBta,Xtb=b+∫0tu(Xsb,s)ds+νBtb, with the same viscosity ν≠0 and the same drift u(x,t)=(ta(x)v1+(1?p)ρtb(x)v2)/(ta(x)+(1?p)ρtb(x)), where ρta,ρtb are respectively the density of Xta and Xtb. Here a,b,v1,v2Rd and p∈(0,1) are given. We show that t(x)=pρta(x)+(1?p)ρtb(x),u(x,t):t?0,x∈Rd) is the unique weak solution of the following pressureless gas system
S(d,ν)?t(ρ)+j=1d?xj(ujρ)=ν22Δ(ρ),?t(uiρ)+j=1d?xj(uiujρ)=ν22Δ(uiρ),?1?i?d,
such that ρt(x)dx→pδa+(1?p)δb,u(x,t)ρt(x)dx→pv1δa+(1?p)v2δb as t→0+. To cite this article: A. Dermoune, S. Filali, C. R. Acad. Sci. Paris, Ser. I 337 (2003).  相似文献   
10.
For a large class of infinite discrete semigroups, we prove that right cancellative points in β S can have arbitrary norms or sizes. More precisely, if for x∈β S, we let ||x||= min{|A| : x
}, and for each infinite cardinal κ, we let P κ (S)={x∈β S : ||x||=κ} then the set of points in P κ (S) which are right cancellative in β S has an interior which is dense in P κ (S). The method to prove this result enables us also to calculate the already known cardinal of the pairwise disjoint left ideals in β S : 2^ 2 |S| . We give an application to the Banach algebra ∈fty (S) * , by showing that the vector space dimension of any non-zero right ideal in this algebra is at least 2^ 2 |S| .  相似文献   
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